Building drum

ABSTRACT

Building drum for tires, bands or laminate structures. Drum is driven by a rotary power shaft. Each segment for forming the building surface is post mounted for radial movement and carries cam followers engaging cam channels mounted coaxially of a hub connecting the drum to the power shaft. The segments are expanded by and collapsed by relative motion of the hub and the power shaft.

United States Patent [191 Lohr et al.

[ Dec. 18, 1973 4] BUILDING DRUM [75] Inventors: Herb R. Lohr, Akron;Toby Magos,

Jr., Kent, both of Ohio [73] Assignee: Akron Standard Division ofEagle-Picher, Industries, Akron, Ohio [22] Filed: June 3, 1971 [21]Appl. No.: 149,509

[52] US. Cl 156/417, 156/1281 [51] Int. Cl B29h 17/14, B29k 17/16. [58]Field of Search 157/141, 142, 146; 156/414, 417, 420

[5 6] References Cited UNITED STATES PATENTS 1,479,005 1/1924 Pearson.[156/417 x 2,996,108 8/1961 Beeber 156/417 X 2,980,160 4/1961 Deibel156/415 3,140,216 7/1964- Shilts et a1. 156/415 X 3,644,162 2/1972Appleby et a1. 156/415 Winzer et a1. 156/415 Primary ExaminerAlfred L.Leavitt Assistant Examiner-C. B. Cosby Att0'rneyMack D. Cook, 11

,[ ABSTRACT Building drum for tires, bands or laminate structures. Drumis driven by a rotary power shaft. Each segment for forming the buildingsurface is post mounted for radial movement and carries cam followersengaging cam channels mounted coaxially ofa hub connecting the drum tothe power shaft. The segments are expanded by and collapsed by relativemotion of the hub and the power shaft.

2 Claims, 4 Drawing Figures PAIENIEBnEc 18 I975 SHEET 101 2 FIG.

INVENTORS HERB R. LOHR TOBY MAGOS JR.

PATENIEUUEC 18 I975 m 2 or 2 INVENTORS HERB R. LOHR TOBY MAGOS JR.

BUILDING DRUM BACKGROUND OF THE INVENTION The present invention relatesto a collapsible drum for the building of tires, bands or laminatestructures. The field of art to which the invention pertains isillustrated by U. S. Pat. No. 2,980,160.

Collapsible building drums according to the prior art comprise aplurality of peripheral segments for mounting around the rotary powershaft of a tire building machine to expand to form a continuous buildingsurface and to collapse to reduce the drum diameter for re moval of thetire or bands or components therefrom.

Heretofore, various mechanisms have been designed to expand and collapsethe peripheral segments. Such mechanisms have not functioned so thatexpansion and collapse of the segments will occur in a gradual andcontrolled manner. Further, the prior art mechanisms have been subjectto undue or excessive wear requiring extensive maintenance.

A further disadvantage of the prior art mechanisms has been that duringexpansion and collapse of the segments the building surface would bedistorted so as not to consistently maintain the dimensional accuracyrequired for the precision building of uniform tires, bands or laminatestructures.

SUMMARY OF THE INVENTION The object of the invention is to provide animproved building drum wherein the peripheral segments will be expandedand collapsed by turning forces applied relative to the power shaft of atire building machine.

A further object of the invention is to provide a building drum whichmay be dynamically actuated whereby the inertial and centrifugal forcesgenerated during and by stopping and starting of the power shaft of atire building machine will collapse and expand the seg ments which formthe building surface.

A still further object is to provide a building drum whereby expansionand collapse of the segments occurs in a gradual and controlled mannerso that the mechanism is not subject to undue or excessive wear.

' A still further object is'to provide a mechanism for a collapsiblebuilding drum with a capability of maintaining the dimensional accuracyrequired for the precision building of uniform tires, bands or laminatestructures.

These and other objects of the invention, and the advantages thereof,will be apparent in view of the Description of the Preferred Embodimentas set forth below.

In general, a building drum according to the invention has a pluralityof peripheral segments for mounting around the rotary power shaft of atire building machine to expand to form a continuous, concentric anddimensionally precise building surface and to collapse to reduce thedrum diameter for removal of the tire band or annular component. Thedrum has a hub or axial sleeve adapted for mounting on the power shaft.

A building drum according to the invention is characterized in that eachsegment is slidably mounted for radial movement relative to therotational axis of the power shaft on guide posts projecting outwardlyfrom the attachment hub. Each segment also has actuator flangesprojecting inwardly toward the hub. The hub coaxially carries radiallydirected plate means having a plurality of skewed curvilinear camchannels thereon.

flange and engaged within each cam channel whereby upon relative motionof the power shaft and the hub the segments will expand and collapse.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view in section ofabuilding drum according to the invention cantilever mounted on the powershaft of a conventional tire building machine;

FIG. 2 is an end view of a building drum according to the invention inthe expanded condition taken substantially as indicated on line 2-2 ofFIG. 1;

FIG. 3 is an end view of a building drum according to the invention inthe collapsed condition; and

FIG. 4 is a fragmentary view taken substantially as indicated on line 44of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT A drum according to theinvention is indicated generally by the numeral 10 and has a continuous,concentric and dimensionally precise building surface 11. The buildingsurface 11 is formed by the radial movement or expansion of a pluralityof interfitting and alternating long and short peripheral segments 12and 14. As is conventional, each peripheral segment 12 and 14 may carrycover or shell plates (not shown).attached in a suitable manner tofurther define the building surface. The exact dimensionalconfigurations of the shell plates are determined by the designrequirements of the tire, band or laminate structure to be built on thedrum 10. As shown, there are a series of six peripheral segments 12 and14 for a conventional tire building machine (TBM).

The rotational axis of the segments 12 and 14 is a power shaft 15 of aconventional tire building machine (TBM). The power shaft 15 extendscoaxially through a hub or axial sleeve 16 which is the primary axialcomponent ofa building drum 10. The hub 16 is connected to the powershaft 15 through a drive means referred to generally by the numeral 17.The drive means 17 applies a turning force to the hub 16 but alsopermits a limited relative motion of the power shaft 15 and the hub 16which is connected to a brake means referred to generally by the numeral18. As shown, the braking connection for the hub 16 is via a coupling 19on the hub 16 to a shaft 20 extending from the TBM and coaxiallyenclosing the power shaft 15. Interiorly of the TBM, the shaft 20 may beselectively engaged by conventional braking elements to at leastmomentarily interrupt or arrest rotation of the hub 16 with the powershaft '15.

As shown, each of the six segments 12 and 14, are alternately mountedradially of the power shaft 15 on a pair of guide posts 21. The base orinner end of each guide post 21 is carried by an annular collar 22. Eachof the two collars 22 is mounted around and secured to the hub 16. Theouter or segment mounting end of each guide post 21 is slidably receivedwithin a bore 23 in a boss 24 on the inner side of each segment. Each ofthe segments also has a pair of actuator flanges 25 between the bosses24 and projecting radially inwardly toward the hub 16.

For the six segments 12 and 14 there are a pair of annular plate means26 for cooperative association with the segment actuator flanges 25.Each plate means 26 projects radially outwardly of the hub 16 inoverlapping A cam follower means is carried by each actuator v relationwith an adjacent actuator flange 25. Referring to FIG. I, each of thetwo plate means 26 may comprise a radially directed element having aflange 27 securely attached to a common base element 28 rotatablymounted around the hub 16.

Referring to FIGS. 2 and 3, each of the two plate means 26 has six camchannels. Three cam channels 29 are for guiding movement of the longsegments 12. Three cam channels 30 are for guiding movement of the shortsegments 14. Each of the channels 29 and 30 begins at a point adjacentor near to the rotational axis of the power shaft 15. Each of thechannels continues outwardly away from the rotational axis to terminatenear the outer edge of a plate means 26. Upon relative motion of thepower shaft 15 and the hub 16, each of the channels functions as avariable pitch scroll cam having a generally spiral or skewedcurvilinear orientation.

As shown in FIG. 3, the short segments 14 collapse inwardly of the longsegments 12. Accordingly, the cam channels 30 for guiding movementof theshort segments have a pitch or degree of inclination r slope, relativeto the rotational axis of the power shaft 15, which is greater than thepitch or degree of inclination or slope of the cam channels 29 forguiding movement of the long segments. That is, the channels 30 have alesser degree of curvature relative to the rotational axis of the powershaft than the channels 29.

As best shown in FIG. 1, the actuator flanges of each of the sixsegments 12 and 14 are interconnected to the plate means 26 on the hub16 by a cam follower means referred to generally by the numeral 31. Eachof the six cam follower means 31 may comprise a shaft 32 carriedtransversely between the radially inward ends of the actuatorflanges 25and having projecting ends 33 interfitting within the cam channels 29and 30.

Referring to FIG. 4, as shown, the drive means 17 for applying a turningforce to the hub 16 but also permitting a limited relative motion of thepower shaft 15 and the hub 16 may be in the form of a bolt or key 35.The bolt 35 may be inserted into the shaft 15 and movable in an arcuateslot 36 in the hub 16 and a mating slot 37 in the base element 28. Thebolt 35 and the slots 36 and 37 are shown in chain lines in FIG. 4. Thelength of the slots 36 and 37 is such as to permit the cam followermeans 31 to fully traverse the cam channels 29 and during expansion andcollapse of the peripheral segments 12 and 14.

Still referring to FIG. 4, the cam channels 29 and 30 may be fitted withreplaceable and adjustable wear plates 38. The plates 38 may beprecisely adjusted using various conventional fastening elements asshown.

What is claimed is:

l. A building drum for a laminate structure comprising a series ofalternating long and short peripheral segments for mounting around arotary power shaft of a building machine and which interfit whenexpanded to provide a continuous, concentric and dimensionally precisebuilding surface and are collapsed to reduce the drum diameter forremoval of the laminate structure, said drum having a hub for mountingon said shaft, each segment being slidably mounted forradial movementrelative to the rotational axis of said shaft on guide posts projectingoutwardly from the mounting hub and having actuator flanges projectinginwardly toward said hub,

characterized in that,

said hub is rotated by said power shaft through a drive means and saidhub is connected to a brake means to at least momentarily arrestrotation of the hub with the shaft,

said drive means permitting a limited relative motion of the shaft tothe hub,

said hub coaxially carrying the radially directed plate means having aplurality of skewed curvilinear cam channels thereon, said cam channelsbeginning at a point near to the rotational axis of the power shaft andcontinuing outwardly to terminate near the outer edge of a plate means,the cam channels guiding said short segments having a pitch relative tothe rotational axis of the power shaft which is greater than the pitchof the cam channels guiding movement of said long segments, there beingcam follower means carried by each actuator flange and engaged withineach cam channel,

whereby, upon said relative motion of the power shaft and the hub thesegments will expand and collapse. 2. A building drum for a laminatestructure comprising a series of alternating long and short peripheralsegments for mounting around a rotary power shaft of a building machineand which interfit when expanded to provide a continuous, concentric anddimensionally precise building surface and are collapsed to reduce thedrum diameter for removal of the laminate structure, said drum having ahub for mounting on said shaft, each segment being slidably mounted forradial movement relative to the rotational axis of said shaft on guideposts projecting outwardly from the mounting hub and having actuatorflanges projecting inwardly toward said hub,

characterized in that, said hub is rotated by said power shaft through adrive means and said hub is connected to a brake means to at leastmomentarily arrest rotation of the hub with the shaft, said drive meanspermitting a limited relative motion of the shaft to the hub,

said hub coaxially carrying radially directed plate means having aplurality of skewed curvilinear cam channels thereon,

said cam channels beginning at a point near to the rotational axis ofthe power shaft and continuing outwardly to terminate near the outeredge of a plate means, the cam channels guiding said short seg mentshaving a lesser degree of curvature relative to the rotational axis ofthe power shaft than the cam channels guiding movement of long segments,there being cam follower means carried by each actuator flange andengaged within each cam channel, whereby, upon said relative motion ofthe power shaft and the hub the segments will expand and collapse.

2. A building drum for a laminate structure comprising a series ofalternating long and short peripheral segments for mounting around arotary power shaft of a building machine and which interfit whenexpanded to provide a continuous, concentric and dimensionally precisebuilding surface and are collapsed to reduce the drum diameter forremoval of the laminate structure, said drum having a hub for mountingon said shaft, each segment being slidably mounted for radial movementrelative to the rotational axis of said shaft on guide posts projectingoutwardly from the mounting hub and having actuator flanges projectinginwardly toward said hub, characterized in that, said hub is rotated bysaid power shaft through a drive means and said hub is connected to abrake means to at least momentarily arrest rotation of the hub with theshaft, said drive means permitting a limited relative motion of theshaft to the hub, said hub coaxially carrying radially directed platemeans having a plurality of skewed curvilinear cam channels thereon,said cam channels beginning at a point near to the rotational axis ofthe power shaft and continuing outwardly to terminate near the outeredge of a plate means, the cam channels guiding said short segmentshaving a lesser degree of curvature relative to the rotational axis ofthe power shaft than the cam channels guiding movement of long segments,there being cam follower means carried by each actuator flange andengaged within each cam channel, whereby, upon said relative motion ofthe power shaft and the hub the segments will expand and collapse.